Project Summary/Abstract Sensory abnormalities have been described since the first reports of Autism Spectrum Disorder (ASD). This sensory dysfunction is now recognized as a core symptom of ASD and has the potential to be extremely debilitating and hinder the development of communication skills in this population. Yet, despite these facts, relatively little is known about the underlying mechanisms of abnormal sensory processing and its specific impacts on social communication. The need for investigation into the roots of sensory abnormalities and their real-world consequences is great, in that increased knowledge in these areas could lead to appreciable improvements in patients? lives. Abnormal sensory processing in sensory-related cerebral cortex as well as supramodal neurophysiologic processes, such as decreased ability to predict sensory events, may underlie both aversive reactions to sensory stimuli and communication deficits. The cerebellum has been implicated repeatedly in ASD, is highly connected to the cortical sensory systems, and plays an important role in prediction of sensory input and language processing. Therefore, this proposal aims to examine the functional connectivity of sensory networks, the cerebellum, and language networks in individuals with ASD and its connection to behavioral measures of sensory reactivity, sensory prediction, and social communication. To this end, first, we will evaluate the resting state functional connectivity of the above networks, and its connection to behavioral measures of social communication in a large, previously collected, and openly-available database of individuals with ASD (n = 83; ABIDE II database). We will also recruit 30 children with diagnosed ASD between the ages of 6-11, and an age- and gender-matched control group (n=30) of typically developing children. These participants will each undergo a resting state fMRI scan and behavioral testing?including measures of sensory reactivity, sensory prediction, and social communication. Resting state functional connectivity within sensory networks and between these networks, the cerebellum, and a social communication network will be calculated and correlated with results on behavioral measures. We hypothesize that sensory cortices will show increased local connectivity, suggesting intensified activity in these cortices. Also, our hypothesis holds that the cerebellum and social communication network will be hypo-connected with sensory cortices. Such results would be consistent with previous findings of decreased long-range connectivity in ASD, and could reflect possible deficiencies in sensory prediction capability, as well as a link between abnormal sensory processing and communication. Finally, we project that the variation in observed functional connectivity will be significantly associated with scores on behavioral measures. Results of the proposed study have the potential to lead to identification of treatment targets and enhance clinical diagnostic / sub- classification methods.